but iam trying the last 3 evenings trying to get a simpler pt2399 work with my lunetta.

I tried the circuits from Phobos (moon base explorer and Pitch shift thingie). No success.

I read mutch about faked pt2399, and not starting oscillating circuits. I triple checked everything. (chips work in a rebote delay)

(why iam posting this in Lunetta forum?) I added two 4040 to the clock out (my scope is over 30 years old, up to 10mhz only). and i get a nice squarewave. (will use this as osc in the lunetta, and some extra blinking). so the osc will start.

the circuits dont work for me with or without a 4040 aded. so wats is the trick?

I run it from my Lunetta power suply a 7805, some caps. and i build a dedicatet (running from 12v adapter..). When i connect a 4093 osc to the input the sound disapear when i power the 2399... (tested diffrent input levels 50k pot)

what means " It is essential that the 5V supply has a low impedance," ?

I don't know what´s causing the problems with the PT2399 (especially since some work and others don't). But I have a circuit you might find useful.
It's a tempo indicator using the CLK out pin and 2x 4040 (as you did) but with the diodes it's set to a specific number so it corresponds with the
delay rate. I think I got it from this thread. note that you have to use the 74HC4040, the CD4040 isn't fast enough.

in my case the 4040 shud work. the datasheet of the 2399 say 10,5k resistor == 4,5 Mhz. the 4040 can handle 7Mhz (at 5V) so the 4040 shud work for evrybody who uses delays longer than 97ms (5,8k resistor) i think. (was try to figure out why its working the last 15min ... )

in your circuit i dont get realy what the diodes doing there. (they keep the output high, but why?)
i using Q12 and Q7 == 19 stages (Q5 is only for some optical fx )
your schematic uses Q10 and Q10 == 20 Stages - or do the diods somthing with the dividing? (i think my 19 Stages exact on the repeat of the echo, i testet with a short "ding sound" and watch the LED)

i googled pt2399 and 4040 after thinking about the divider and found this:

yeah I think you're correct, as long as you don't make the delay times to short it should work with a regular 4040. I know when I made the indicator
years ago it didn't work very well, untill I replaced the 4040 with 74HC4040's.

The diodes + pullup resistor function as a AND gate and are there to reset the counter once it has reached a specific number. As long as one of those
outputs is low the reset pin will be held low, only when all of those outputs are high the reset pin will be made high.
For the first counter it's 2^4 + 2^6 + 2^7 + 2^8 + 2^9 + 2^10 = 2000.
For the second counter it's 2^3 + 2^4 + 2^6 + 2^8 +2^10 = 1368
which makes the total count 2000 x 1368 = 2736000.

now if you look at the datasheet there is a table with the delay time and VCO frequency. I't not really linear so with a fixed divider it won't be exact
but it comes close. For a delay of 342mS the CLK out is 2MHz. 342mS -> 2.92Hz so the LED should flash at this rate. 2000000 / 2736000 = 0.73Hz
which seems too slow but 0.73Hz is exactly 2.92Hz / 4, so either it flashes at 1/4 of the actual delay rate or my calculations are off
It would make sense to divide it by 4 since it would flash rather fast if you didn't.

yeah, you'll probably have to make custom parts quite often. Even the ones in the library aren't always useful. But you can select the component, then
go to "Component" > "Ungroup component", change it and then choose "Group to make component" which can save some time compared to drawing
it from scratch. And you can save it as custom component for future use. Also if you connect lines to eachother (cross or T) it doesn't always connect
them and then it doesn't show a dot on the connection when you export the schematic._________________"My perf, it's full of holes!"http://phobos.000space.com/http://www.acidtrash.com/Stickney Synthyards

mhm the osscilator is starting (i checked that with scope and the two 4040) i use a 12k resistor and a 50k pot. (other ppl use 2,2k and get starting problems with the osc.)

i dont investigate this any more ... it must be the PT2399... not me and not the circuit. (i change one from the not working to my rebote delay and still got 4 working here.... thats enouth echo for the next days )

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